The effects of methylxanthines on the mobility of stored turkey sperm

Liquid semen storage-induced alteration in the protein composition of turkey (Meleagris gallopavo) spermatozoa

Liquid storage of turkey semen without the loss of fertilizing ability is of practical interest to the poultry industry. However, fertility rates from liquid-stored turkey semen decline within a few hours. A clear cause of the decline in spermatozoa quality remains unidentified. Therefore, the purpose of the present study was to monitor the dynamics of proteomic changes in spermatozoa during 48 h of liquid storage by 2-dimensional difference in-gel electrophoresis coupled with matrix-assisted laser desorption/ionization mass spectrometry. A total of 57 protein spots were differentially expressed between fresh and stored spermatozoa; 42 spots were more and 15 were less abundant after 48 h of semen storage. Raw proteomic data are available via ProteomeXchange with identifier PXD043050. The selected differentially expressed proteins (DEPs) were validated by western blotting and localized in specific spermatozoa structures by immunofluorescence, such as the head (acrosin and tubulin α), midpiece (acrosin, aconitate hydratase 2, and glycerol-3-phosphate dehydrogenase) and tail (tubulin α). Most of the DEPs that changed in response to liquid storage were related to flagellum-dependent cell motility, energy derivation through oxidation of organic compounds and induction of fertilization, suggesting the complexity of the processes leading to the decrease in stored semen quality. The damaging effect of liquid storage on spermatozoa flagellum manifested as more microtubule proteins, such as tubulins and tektins, most likely formed by posttranslational modifications, tubulin α relocation from the tail to the sperm head, which appeared after 48 h of semen storage, and decreases in fibrous shelf proteins at the same time. Motility could be affected by dysregulation of Ca2+-binding proteins and disturbances in energy metabolism in spermatozoa flagellum. Regarding sperm mitochondria, DEPs involved in energy derivation through the oxidation of organic compounds indicated disturbances in fatty acid beta oxidation and the tricarboxylic acid cycle as possible reasons for energy deficiency during liquid storage. Disturbances in acrosin and 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase zeta may be involved in rapid declines in the fertility potential of stored turkey spermatozoa. These results showed the complexity of the processes leading to a decrease in stored semen quality and broadened knowledge of the detrimental effects of liquid storage on turkey spermatozoa physiology.

Aqueous seed extract of Cola nitida rubra reduces serum reproductive hormone concentrations and sperm count in adult male albino Wistar rats

Background:

Following the high rate of consumption of Cola nitida (cola nut) among the male population in Nigeria, this study seeks to determine the effects of consumption of Cola nitida on serum reproductive hormones and sperm count, which are major determinants of male fertility.

Materials and Methods:

Thirty-two male albino wistar rats weighing 180-220 g were used for this study and were divided into 4 groups of eight animals each. Group 1 served as control, group 2 received 2 mg/kg Cola nitida extract (Test 1), group 3 received 6 mg/kg Cola nitida extract (Test 2) and group 4 received 10 mg/kg Cola nitida extract (Test 3). After 6 weeks of treatment, reproductive hormonal assay was carried out using the rat serum. Epididymal spermatozoa were collected and sperm count determined.

Results:

Serum concentrations of luteinizing hormone (LH) and testosterone were significantly (P < 0.05) reduced in test 2 and 3, compared with control. Sperm count was significantly lower in test group 1 (P < 0.05), 2 (P < 0.001) and 3 (P < 0.001) compared with control, with test 3 significantly (P < 0.05) lower compared with test 1. There was no significant difference in testicular and epididymis weight in the different experimental groups studied.

Conclusion:

Aqueous seed extract of Cola nitida rubra resulted in reduced serum reproductive hormone concentrations and sperm count in male wistar rats, and may therefore be detrimental to reproductive health, hence the need for regulation of its consumption.

Improvement of stored turkey semen quality as a result of He–Ne laser irradiation

Two experiments were carried out to evaluate the effects of He-Ne laser irradiation at various energy doses on the quality of stored turkey semen. Four semen pools were used in Experiment 1. Each pool was divided into 10 aliquots, nine of which were irradiated with energy doses ranging from 0.144 to 10.8 J/cm2 while the tenth one was not irradiated (control). Each sample was evaluated for motility immediately after irradiation, 24 and 48 h later. Energy doses ranging from 3.24 to 5.4 J/cm2 had higher (P <0.01) sperm motility index (SMI) value compared to the control and samples irradiated with lower and higher laser doses. The energy dose of 3.96 J/cm2 was selected for Experiment 2 to obtain further insight on its effects on turkey sperm preservation for up to 60 h. Each pool of four semen was divided into two aliquots: one represented the control and the other one was irradiated with He-Ne laser at an energy dose of 3.96 J/cm2. Each sample was evaluated for motility and viability immediately after irradiation and then at 12 h intervals up to 60 h. The cell energy charge was also measured by HPLC. Exposure to 3.96 J/cm2 increased the SMI and viability of turkey semen stored for 60 h compared to the control (P <0.05). The cell energy charge of irradiated samples was 200% higher than in the control. Laser irradiation increased the longevity of stored turkey spermatozoa, and might be a useful technique to enhance semen quality in long-term storage.

Prostaglandin levels in seminal plasma and sperm extracts of the domestic turkey, and the effects of cyclooxygenase inhibitors on sperm mobility

BACKGROUND

Turkey reproduction is by artificial insemination using pooled semen so there is interest in storing semen. Fertilizing capacity declines after six hours storage, possibly due to poor sperm mobility. Prostaglandins (PG) affect mammalian sperm motility, but avian sperm has not been widely studied. For this study, levels of PG E1, E2, and F2 alpha in turkey seminal plasma and sperm extract, and effects of cyclooxygenase (COX) inhibitors on sperm mobility were determined.

METHODS

Seminal Plasma and sperm extract PG E1, E2, and F2 alpha, from 1.0 mL pooled semen, were measured by ELISA. In Trial 1, PG were determined from 122 wk old toms (n = 4). Trial 2 used 36 wk old toms (n = 7). For Trial 3, PGE2 only was measured from 48 wk (n = 6) and 154 wk old toms (n = 3). The effects of non-specific COX inhibitors indomethacin, diclofenac, tolmetin, or aspirin (n = 10), or specific COX-1 or COX-2 inhibitors (n = 3) on sperm mobility were measured (Accudenz swim-down test).

RESULTS

Seminal plasma PG (pg/mL) in Trials 1 and 2, respectively, were 185.2 +/- 88.4 and 187.2 +/- 33.7 for PGE1; 141.4 +/- 43.1 and 100.4 +/- 14.6 for PGF2 alpha; and 431.0 +/- 155.1 for PGE2 (Trial 1 only). Sperm extract PG (pg/10 billion cells) in Trials 1 and 2, respectively, were 215.1 +/- 38.1 and 208.9 +/- 41.5 for PGE1; 133.7 +/- 51.7 and 49.8 +/- 8.3 for PGF2 alpha; and 52.3 +/- 8.6 for PGE2 (Trial 1 only). In Trial 3, seminal plasma PGE2 (pg/mL) in older versus younger males was 1097.9 +/- 99.3 versus 853.2 +/- 144.6 and sperm extract PGE2 (pg/10 billion cells) was 208.0 +/- 56.1 versus 102.4 +/- 14.8. Cyclooxygenase inhibitors (0.001 to 10 mM) decreased sperm mobility: indomethacin 15 to 100%; diclofenac 4 to 100%; tolmetin 27 to 74%; aspirin (tested at 0.01 to 15 mM) 22 to 42%; resveratrol (COX-1) and NS-398 (COX-2), both tested at 0.1 to 10 mM, 38 to 98% and 44 to 85%, respectively.

CONCLUSION

These results indicate that PG are present in turkey seminal plasma and sperm, and COX inhibitors decrease turkey sperm mobility.

Production and characterization of a turkey sperm mitochondrial monoclonal antibody and its usefulness for assessment of sperm integrity

A monoclonal antibody (4C7/2E4) that binds to an antigen located on the midpiece of turkey spermatozoa has been produced and characterized. The antibody was also reactive to antigens on the midpiece of chicken, Japanese quail, and bobwhite quail spermatozoa but was unreactive to spermatozoa from guinea fowl, human, horse, boar, and bull. Immunogold transmission electron microscopy of turkey spermatozoa showed that the antibody was associated with the outer mitochondrial membrane. Titratable antibody binding was observed for extracts of turkey spermatozoa and isolated mitochondria. The antibody did not recognize proteins separated by SDS-PAGE, but on Western blots of proteins separated by native gradient-PAGE, the antibody recognized a broad band greater than 660 kDa. No effects on fertilizing capacity, embryonic mortality, or hatchability of eggs were observed when the antibody was added to turkey semen prior to insemination. When semen stored for 0, 3, 6, 24, and 48 h was immunolabeled with 4C7/2E4, the percentage of spermatozoa with unlabeled midpieces was significantly increased by 6 h of storage. The number of free mitochondria and damaged midpieces also significantly increased with storage.